linux: January 2013

Friday, January 25, 2013

Linux Booting problems

The Linux box not able to boot due to external file system errors

Loggin to single user mode # all file systems other than vg00

a.) interrupt the normal booting process & enter into grub menu
then choose the kernel version you want to boot select it press enter. choose the second line starting
with kernel and press e to edit. At the end of the line after one space put 1 (press enter key to save the changes) then b to boot in single user mode

b) After it prompts for logging password enter root password and mount root file system in read write mode

mount -o rw / or munt -o remount,rw /
cp -p /etc/fstab /etc/fstab_25jan
/usr/bin/vim /etc/fstab
(# all other file systems other than vg00)

reboot the server.

Linux kernel panic recovering through maintenance mode

Boot the Linux OS through installation media and select recovery .

Script For Searching alerts in Syslog and Dropping a mail

#!/usr/bin/sh
#################################################################################
# Script Name : syslog_error_chk.sh #
# #
# Description : Searches for errors in syslog and mail . #
#################################################################################

Unix Interview Questions

How to convert a ext2 file system to ext3 ?

What modprobe will do in Linux ?

what is the use of kudzu ?

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How to print two files columwise in third file ?

paste -d' ' file1 file2

How to check different error count in a log file ?

Maintain error count record and if the error count is more than previous ignore. if the error count is less than previous reset the counters.

How to reverse a string or check weather its a palindrome or not ?

string_new = rev string1 #### it gives the reverse of the string.
test string_new = string1; if [$? -eq 0] ;then do echo "its a palindrome";fi

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1) Tell me about yourself ?

2) tell me your day to day activities ?

3.) replacing a boot disk ?

4) patching HP-Ux ?

5) Hardware models you worked on ?

6) processor of Hp9000 series ?

7) How do you trouble shoot ?

8) script to cut a particular field ?

9) script to print a file reversely ?

tail -r myfile.txt

or
tac reverse of cat

tac myfile.txt

10) perl scripting exp >. ?

11) Disk addition ?

12) Disk addition in cluster ?

13) creating a software depot ?

14) checking model /

15) do you have any specific questions ?

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Tell me about your work .. ?

Rate yourself in Perl Scripting and Shell scripting ?

How you write modules in puppet ?

About exadata & Data Ontap ?

Perl Scripting:

-- > Autoloader ?

---> Difference between a module and package ?

Tell me about your environment in puppet ?

How to configure password less ssh ?

Any Other Questions to Ask ?

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Tell me about yourself?

How do you rate on scale of 1-10?

Hp Service Guard?
How to configure a package?

How do you mirror lv?

How do you restore a failed disk?

what is major number ? minor number ?